How can I show only last Versions of photos edited by elements in mobile Albums (and retain all Versions in elements).

Hi Guido,
Since Mobile Albums are a Photoshop Elements feature (that allows you to connect with Adobe Revel), you should post your question to the Photoshop Elements support page.
You should see a button with a link just to the right of this box =>
Or, you can click here: http://feedback.photoshop.com/photosh....

You may expand the version set and select all (but top of version set) files, right click > Remove from Revel. This would mean the files will become local to EO catalog and only top of the version set would be available on Revel.